Intensity maps. First row: 353-GHz map from Planck downgraded at N_side = 64 and the corresponding map of uncertainties that we use to compute the χ². Rows two to four correspond to dust density distribution models labeled ED, ARM4, and ARM4⊕ED, respectively.The obtained best-fits are shown in the first column and the statistical significance of the residual, per-pixel, are shown in the second column.